Protractor means for cutting or sawing machines



w. w. GARDNER Jan. 2, 1945.

PRQTRACTOR MEANS FOR CUTTING OR SAWING MACHINES Filed Ju1.y 17, 1942 {ZERO POSITION FIG F'IG.5. INVENTOR.

. WALLACE GARDNER X; W lfi llllll QBY A T TORNE Y5 Patented Jan. 2, 1945 asssisrz:

cRorRAc'roaMnANs Fomouirrrma on} l s-AwrN-G MACHINES; i

Wallace'W! Gardner, Lancaster, Pa., assignor to De Walt Products Gcrpora-tion; Lancaster, Pa, aicorporation of P'ennsyl vania.

.; Thisinve n'tion reIatesQtQimproVements in saw.-

ing or cutting. machines and moresparticularly to improvements in means for indicating thaangularity at which a part of the machine. extends the top, thereofa horizontally extending arm H: which, can be locked in. places bye: latching memxbet m ther cooperatingi pants. otwhich are. not. illustrated. Elevation. of the columniand the 1 arm,

relativetc-another part, 5. as=a unit cantbe;accomplished:byrthacrankv M. An. objects-f. the presentinyention ism-provide and. locking of the .armand. column in. adjustedv conveniently located, readily. visible means.- for vertical positionycarrbecontrolled bythehandle indicatingtheangleat which a-partot amachine t5! (the: cooperating parts being; omittedhg extendsin relationto another partand for.simu1. Slideably supported. by the arm it is) a motor. taneously. indicatinglthe manner in whichrraf-ters i1? YOke L6. in which is suspendediaz motor llg driving and thelike,can..be,cutffor desiredapurposesr asawor otherrotatable; cutting; elementz; Inase Another objector .theinvention. is, to provide much as thepartsheretofore mentioned jformino. i in combination with armachine of the. .foregoing part of this presentinvention, they havelnotbeen character meansifor. indicating. simultaneously on illustratedin detailsince, f-or" thelmostpart they 'eachofna plurality otscal'esl varlious angular. relax- 5 areot conventionaLcharacten i ticns. cfa cuttmgpartiot themach ine. The, improvement incorporated in this; invene Another object. of theinyention. isto provide tion. consists. of a scaleecarrying membenZ-fl and; on: a single member. a plurality of scales. which acooperatingpointer 21|.-,.the scale carrying mem1- can beusedseie'ctively-for determining. the angle ben being securedto. an: upn j part, or head at which. the ends,ot"a.. rateror similar. member. (20 2.2. of. the; columntwhile the pointer. 2=l is secured canbecut, l a. I 3 to. the .arm .I I; Referring; now to FigsiZY to 5 A further. object-oi the. invention isto. provide inc1usi-ve,,,it will be. seenthat the. scale-carrying means for, attaching. theoscale-carrying. member member 210 is madeiof thinmetalior other suitable l to. a partofi a. machine. with adjustment being. materiall which. is bentzintopartial circular form. possible for orienting such. scale. relative; to. at stop. to; fit: partially aroundi the head 2'2, which is; cironthe. machines, 1 cularimcross sectiona In: order that the member. A still iurther objectof.the. invention. is to Zllicanbe-adjustablysecured toithishead 22', use provide, simplified meanstor.attachingthescaleis; made eta small rabbeted member 24 secured carrying member. to. .themachine for. adjusting to. the lower portion of r the exterior ofthe-headi the samerelativeto.themachine. '30 Zlby-a plurality of screws, 25.. The; member .20, A still. furtherobject. of the invention is to. is provided in each. end with: a, slot 25 for the provide simplifiedcooperating indicating means passageof: agheaded-screw member Zitwhich; is: for visibly indicating to theoperator the angular threaded into the head 22. The slots 26 are so relation of the various parts of the machine. disposed relative to the screws 21 and to the bot- Other features, objects, and advantages of the tom edge of the member 20 that the bottom invention will become apparent by reference to portion of the member 2a is retained in the space the following detailed description of the same provided by the rabbeted member 24, which rahi wherein i beted member serves to maintain the member 20 Fig. l is a side elevationoi a part of a machine in curved form against any tendency of the same showin t e inv n pp ie ther o; to depart from such curved form. The purpose e 2 is a enla d p n iew of a p rt of of this adjustable connection of the member 20 i the i e ShOWn in y to the head 22 will be explained in detail later. 3 is a pa from View in an e gement The pointer 2|. is made up of an angle piece indiof the scale mechanism shown in Fig. 1, such view cated at 30, one leg of which is provided with being taken from p t A l a pair of openings 3| for the passage of screws F 4 is an enlarged elevation taken from the to attach the pointer to the upper surface of the point B of 2; arm II. The other leg of the member 30 has Fig. 5 is a section taken substantially on the secured thereto a tapered member 32 of some suitv line 5-5 of Fig. 4; and able transparent material such as a plastic or Fig. 6 is a perspective view of the pointer used any other material which will serve the purpose. in the invention. Extending vertically on the member 32 is a thin Referring now to the drawing, It indicates gen line 34 which serves as an indicator in coopera erally a vertical column or supporting member tion with the scale-carrying member 20.

for a machine or more or less conventional char- The scale-carrying member 20, as shown clearacter. This column has rotatably mounted at ly in Fig. 3, has three scales thereon. The upper of these scales indicated at 35 is graduated for the purpose of aiding an operator in cutting rafters of the type known as hip or valley rafters. Each mark on this scale 35 indicates to an operator that such mark represents a rise of one inchper seventeen inches of run of the rafter or, in other words, if the arm II is moved into such position that the line 34 coincides with the graduation mark 2 on scale 35, then a rafter cut by the saw operated by motor l'l would have an end of such angularity that when properly installed in a building, the rafter would have a rise of two inches for each seventeen inches of run of the rafter. I

The second scale 36 has graduations thereon for the purpose of determining the angle at which the end of a rafter can be cut, such rafters being of the type known to the art as common or jack rafters. Each graduation of the scale 36 indicates to an operator a rise of one inch per foot of run, or in other words, if the pointer 34 should be aligned with the'graduation mark 2 on scale 36, an operator would know that the end of the rafter would be cut at such angularity that when installed in place, it would have arise of two inches per foot of run. A third scale 31 is graduated in degrees so that an operator can align the thin line'34 of the pointer with any desired degree of graduation to obtain a cut of any desired angularity. It should be noted that 'the indication is clearly visible to an operator is in alignment with the line 34 of the pointer 2|. When such alignment has been attained, the set screws 21 can be tightened, locking the scalecarrying member in place. In this fashion, the three scales can be oriented simultaneously relative to any operating conditions of the arm as might be required by the positioning of a back stop on the work table.

From the foregoing, it will be seen that the present invention provides a new, simple, and efiicient means whereby angular relations between parts of a machine can be simultaneously indicated for various purposes and such indicating means can be oriented as desired. The scale being positioned at the topmost part .of the machine is readily visible, and since it is provided with a vertical surface located above the saw, sawdust does not readily collect on the scale and obscure it. It will be understood that the invention is not to be limited to the illustrated embodiment since it is capable ofmodification but is to be limited only by the scope of the following claim. p

as to the set of the arm ll relative to either one of the three scales simultaneously.

Inasmuch as machines of this character usually employ tables having stops thereon against which the material being processed is adapted to rest, and since such stops may become worn slightly and throw the work out of true angular disposition relative to the arm II and to the column I0, the present invention makes possible the orienting of the scales'carried by the member 20 relative to this stop. For example, should the table stop become so worn that an initial setting of the scales is no longer accurate, a protractor could be employed in connection with the table stop and the arm adjusted until the saw carried thereby moves in a path directly and truly at right angles to the table stop. When such condition has been assured, then the scalecarrying member 20 can be adjusted by loosening the screws 21 and moving the captive member 26 until the zero position on all three scales I claim:

In a woodworking machine having a supporting column, a horizontal arm supported by said column and swingable in a horizontal plane about a vertical axis established by the column, and asaw suspended from said arm and adapted to cut the work material at an angle determined by the radial position of said arm; the improvement which comprises: a vertically disposed scale strip partly encircling said column in coaxial relation thereto, the scale strip being above said arm and being provided with parallel series of graduations to indicate angles for different types of cutting operations, and an index mem ber attached to said arm and cooperating with all of the series of graduations on the scale strip 40 to indicate the radial position ofsaid arm whereby the arm may be set to position the saw for making a cut at a desiredangle according to any of said series of graduations, the shape of the scale strip and its position above the arm and 

